Check for DC voltage at the collector/drain of the final RF power transistor during PTT engagement.
Often caused by a failing PA MOSFET (typically HTL7G06S011P ) or "cold" (cracked) solder joints on the heatsink-mounted components. qyt kt-7900d service manual
Ensure the squelch isn’t locked out via software corrupted EEPROM data. Perform a factory reset. Check for DC voltage at the collector/drain of
If you want, I can: